Caption: Methamphetamine drug, molecular model. Methamphetamine (C10H15N) is a stimulant and euphoriant that is illegal in most countries. It is known by the slang names speed , crystal meth and ice , amongst others. Atoms are shown as spheres and are colour-coded: carbon (turquoise), hydrogen (white) and nitrogen (blue). It is generally snorted as a powder, smoked or dissolved and injected. Frequent use of the drug can lead to addiction and dependence.